IPUtils.java

package com.dianping.puma.biz.util;

/**
 * Project: puma-server
 * 
 * File Created at 2012-7-24
 * $Id$
 * 
 * Copyright 2010 dianping.com.
 * All rights reserved.
 *
 * This software is the confidential and proprietary information of
 * Dianping Company. ("Confidential Information").  You shall not
 * disclose such Confidential Information and shall use it only in
 * accordance with the terms of the license agreement you entered into
 * with dianping.com.
 */
import java.net.Inet6Address;
import java.net.InetAddress;
import java.net.NetworkInterface;
import java.net.SocketException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Enumeration;

/**
 * @author Leo Liang
 * 
 */
public final class IPUtils {

	private IPUtils() {

	}

	/**
	 * 获取第一个no loop address
	 * 
	 * @return first no loop address, or null if not exists
	 */
	public static String getFirstNoLoopbackIP4Address() {
		Collection<String> allNoLoopbackIP4Addresses = getNoLoopbackIP4Addresses();
		if (allNoLoopbackIP4Addresses.isEmpty()) {
			return null;
		}
		return allNoLoopbackIP4Addresses.iterator().next();
	}

	public static Collection<String> getNoLoopbackIP4Addresses() {
		Collection<String> noLoopbackIP4Addresses = new ArrayList<String>();
		Collection<InetAddress> allInetAddresses = getAllHostAddress();

		for (InetAddress address : allInetAddresses) {
			if (!address.isLoopbackAddress() && !address.isSiteLocalAddress()
					&& !Inet6Address.class.isInstance(address)) {
				noLoopbackIP4Addresses.add(address.getHostAddress());
			}
		}
		if (noLoopbackIP4Addresses.isEmpty()) {
			// 降低过滤标准，将site local address纳入结果
			for (InetAddress address : allInetAddresses) {
				if (!address.isLoopbackAddress() && !Inet6Address.class.isInstance(address)) {
					noLoopbackIP4Addresses.add(address.getHostAddress());
				}
			}
		}
		return noLoopbackIP4Addresses;
	}

	public static Collection<InetAddress> getAllHostAddress() {
		try {
			Enumeration<NetworkInterface> networkInterfaces = NetworkInterface.getNetworkInterfaces();
			Collection<InetAddress> addresses = new ArrayList<InetAddress>();

			while (networkInterfaces.hasMoreElements()) {
				NetworkInterface networkInterface = networkInterfaces.nextElement();
				Enumeration<InetAddress> inetAddresses = networkInterface.getInetAddresses();
				while (inetAddresses.hasMoreElements()) {
					InetAddress inetAddress = inetAddresses.nextElement();
					addresses.add(inetAddress);
				}
			}

			return addresses;
		} catch (SocketException e) {
			throw new RuntimeException(e.getMessage(), e);
		}
	}
}